Water-based compositions, e.g., coating compositions such as paints, that include latex polymer particles or water-dispersible polymer particles typically also include a coalescent (i.e., coalescing agent or film-forming agent) in addition to pigments and fillers, for example. The coalescent functions as a solvent as well as a plasticizer for the polymer particles (to soften the polymer particles and assist in the formation of a continuous coating or film, for example, after applying it to a surface and allowing it to dry).
Useful coalescents are generally stable in the presence of water, compatible with other ingredients typically used in paint formulations, particularly the polymers particles, such that the stability of the water-based composition is not compromised. They are also typically sufficiently volatile to escape when the applied composition is allowed to dry, but sufficiently nonvolatile to evaporate more slowly than other ingredients (e.g., drying retarders, antifreezes) that delay film formation. However, there is a general desire in the industry to reduce volatile organic emissions, thereby reducing the environmental and health concerns.
Governments have established regulations setting forth guidelines relating to volatile organic compounds (VOC) that may be released into the atmosphere. To reduce the level of VOC, new high solids coating compositions have been developed as well as powder coating compositions that do not include volatile compounds, have a reduced concentration of VOC, or incorporate compounds having a lower volatility. Reducing the volatility of coalescents, solvents, plasticizers, etc. can adversely affect the balance of properties needed in a latex-based coating composition, however. Thus, there is a need for coalescents, solvents, plasticizers, etc. used in coating compositions such as paint that do not compromise stability, compatibility, film formation ability, or the desirable properties of the applied coating, etc.